Short‐Term Risk of Pneumonia After Fracture by Anatomical Site in Adults Aged 65 Years or Older: A Propensity Score–Matched TriNetX Cohort Study

AIM: To compare short-term recorded pneumonia risk across fracture sites in adults aged 65 years or older, focusing on thoracic-region versus lumbar-region vertebral compression fracture (VCF). METHODS: This retrospective TriNetX cohort study included adults with a first qualifying recorded diagnosis of one of six fractures. Pair-specific cohorts underwent 1:1 propensity score matching. The primary outcome was at least one recorded pneumonia diagnosis during Days 3-90; Days 3-30 were secondary. RESULTS: After matching, the maximum standardized mean difference was 0.031 or less in every comparison. In the primary analysis, 42 959 patients were included in each cohort. During Days 3-90, pneumonia occurred in 1469 patients (3.42%) after thoracic-region VCF and 1171 (2.73%) after lumbar-region VCF (risk ratio [RR], 1.25; 95% confidence interval [CI], 1.16-1.35); the 3-30-day RR was 1.31 (95% CI, 1.17-1.46). Versus pair-specifically matched distal-radius cohorts, 3-90-day RRs were 2.29 for thoracic-region VCF, 1.91 for lumbar-region VCF, 2.33 for proximal femur fracture, 1.97 for single-rib fracture, and 2.39 for multiple-rib fractures. Multiple-rib fractures had greater risk than single-rib fracture (RR, 1.24; 95% CI, 1.18-1.31). CONCLUSIONS: Relative associations with recorded pneumonia were generally stronger during Days 3-30 than during Days 3-90. Risk was higher in the thoracic-region VCF cohort than in the lumbar-region VCF cohort and in the multiple-rib fracture cohort than in the single-rib fracture cohort. These findings may inform respiratory surveillance based on fracture site and rib-fracture burden, subject to residual confounding and diagnostic-code limitations.